When driving along a route on a road, it is common that a vehicle catches up to another slower vehicle which is driving along the same route in the same direction. In case the road has at least two lanes in the same direction, the faster vehicle may change lane in order to pass the slower vehicle in an adjacent lane.
If a driver of a vehicle is catching up to a slower vehicle on a road with only one lane in each direction, or on a road with a broad common lane for two different driving directions, the driver may intend to overtake the slower vehicle ahead using a lane, or part of a lane, which is normally used by oncoming vehicles, driving in the opposite direction.
During relatively straight road sections, where the vehicle driver can see the road well ahead of his/her vehicle, an overtake of a slower driving vehicle ahead is often relatively easy. During less favorable circumstances, it may be more hazardous to perform an overtake of a vehicle ahead. On winding roads, it may be difficult to overlook the entire distance required for the overtake, since curves and brows of a hill may decrease a visible road section ahead. During conditions with reduced sight, such as during dusk, dawn, night, rain or fog, it may be difficult both to gain sight of the road ahead and to estimate a distance to a detected oncoming vehicle.
It may also be a challenge for a driver to overtake a large vehicle ahead, such as a truck, bus or tractor, since a long vehicle ahead requires longer passing time, and since a broad vehicle ahead may occupy a large portion of a width of the road. In addition, large vehicles may obstruct a big part of the view for a vehicle approaching from the rear.
A situation in which a driver of a faster vehicle catches up to a slower vehicle on a road section where an overtake is difficult or hazardous may be frustrating for the driver in the faster vehicle. If he/she is stressed or inexperienced, there may be a risk that he/she initiates an overtake although conditions are less than optimal if he/she believes that a considerable time amount is gained thanks to the overtake. Thus, improvements in the field of vehicle safety in overtaking scenarios are desirable.